Vaporproof switch casing



Aug. ll, 1931. E. L. BUKER 818038 VAPORPROOF SWITCH CASING Filed Dc. 17, 1928 Patented Aug. 11, 1931 PATENT oFFIcE EARL L. BUKER, F GREAT FALLS, MONTANA V'APOBIPROOF SWITCH CASING Application filed December 17, 1928. Serial No. 826,642.

This invention relates toa push button switch and more especially to a vapor proof casing therefor. One object of the invention is to provide a J switch having a reciprocating 'operating member, the switch being housed within a vapori proof and water-tight casing.

Another object is to provide a vapor-proof, w water-tight/switch casing so arranged that to expose the switch parts without interfering with the wiring connection, thus exposing the complete switch in an operable condition.

Another obj ect is to provide a vapor-proof, water-tight push button switch wherein the operating Apush buttons are sealed by liquid against entrance of -air orvapor, thus' eliminating all packing glands around the buttons..

Another object is to provide a push button casing having an adequate wire entrance compartment for the reception of the wires, and so arranged that air and vapor can be excluded from the switch casing.

These and other objects will be apparent from the following description taken in connection with the accompanying drawings wherein Fig. 1 is a sectional view of the switch, taken on line 1-1 of Fig. 2,

Fig. 2 is a sectional view taken at right angles to Fig. 1 on.v line 2-2 of F ig. 1,

gig. 3 is a section on line 3-3 of Fig. 1, an

Fig. a is a side elevation of the switch.

Referring to the drawings, the switch housing comprises a main casing 1 having a rectangular base 2. Upright walls 3 extend npwardly from base 2. but spaced from the edges of the base to form a receptacle 4 open at its top. A wire-receiving compartment -5 depende downwardly below the rear of base 2, there being provided another upstanding wall 6 extending upwardly from compartment 5 tn approximately the same height as walls. 3. Perforated supporting lugs 7 project outwardly from the rearwall'of compartment 5. by means'of which the switch may be secured against a vertical support;

The base 2 has two openings 8 adapted to one part may be easily and simply removed receive the push buttons of the switch. Cups 9 surrounding openings 8 extend upwardly well into compartment 4. Perforated lugs 10 extend outwardly from base 2 by means of which a cover is secured over the switch.

The structure as thus far described is usually formed of one casting but obviously it may s stantial thickness, so that openings may be drilled and tapped to receive screw-threaded electrical conduit. Thus the electrical wires may enter from either side, the bottom or the rear and the openin can be made vapor-tight at, the screW-threa ed joint 'of the conduit. 4One such conduit is shown and is designated by numeral 11. A i

The compartment 5 is made amply large so that adequate space is provided for the electric Wires, whereby an excess amount of wire may be used, thus avoiding the necessity of pulling in new wires if a new connection becomes necessary at the switch. The wire compartment 5 may be sealed by proper sealing com ound if desired, to thus avoid any posy sibility of the entrance of vapor by means of the wire conduit 11.

The switch contacts are mounted upon an insulating base 12 secured by screws 13 to the walls 3 of base 2. The base 12 has openings 14 positioned above openings 8. Push buttons 15 project through these openings 1 4, the

. stems thereof carrying metallic contact disks 16. Stationary contacts 17 are mounted upon the upper surface of base 12 and project over the push-button disks 16. Y

1n order to guide and support the stems of the pushbuttons, a strap member 18 is secured against opposite walls 3 of base 2, this strap extending over the push-buttons and having openings therein in which guides 19 are secured. These guides 19 receive the ends of the pushbutton stems. Springs 20 surround guides 19 and bear against the pushbuttons to maintain contact disks 16 outvof contact with stationary contacts 17 The operators for push-buttons 15 comprise ste-ms 21 having depending cups 22 secured thereto adjacent their inner ends. These cups are substantially the same length or slightly longer than the upstanding cups 9 and surround cups 9. A sealing liquid 23, such as oil, is poured into compartment 4, this liquid being high enough so that the lower ends of cups 22 secured to buttons 21 never pass out of the liquid. An eiective liquid seal against the entrance of air or vapor is thus provided around the operating buttons.

The complete switch is housed by a rectangular housing 24 having an open bottom. This housing is placed over the switch and clamped against a gasket 25 by bolts 26 and wing nuts 27, the bolts passing through opensided lugs 28 adjacent the ltop of housing 24 and being held against rotation by angular openings in lower lugs 10 for receiving the angular heads of the bolts.

As thus constructed, it will be clear that the switch is completely'housed and sealed against entrance of all air and vappr, whereby the switch parts are kept bright and clean of corrosion. 'The housing 24 may be easily7 removed by loosing thumb nuts 27 and the entire switch is exposed in its operative position so that the buttons 21 may be manipulated to test out the switch.

The switch has beenshown as having a common center contact for` the two push buttons, as on a motor start and stop switch. It will be understood, however, that it is not so limited. It will also be clear that the number of push buttons is immaterial, since a bank of buttons maybe .arranged side by side in a similar casing. Y'

Various other changes may be made in the design of the switch which will fall within the purview of this invention as expressed in the accompanying claims.

1. In a vapor-proof electric switch, a main -casing forming a substantially rectangular compartment having an open end, an insulating base secured to the open end of said casing stationary contacts mounted on said base, a switch "operator comprising a contact and extending through said base, a channelshaped strap secured to the side walls of said casing and projecting upwardly over said base, and guiding means for the switch operator secured to said strap. Y

2. The structure as in claim 1 wherein -aligned openings are provided in the main casing and the insuulating base for the reception of a switch operator.

3. The structure as in claim 1 wherein aligned openings are provided in the maincasin'g and the insulating basefor the reception of a switch operator, sleeves project upwardly around the openings in4 said casing, and a sealing liquid is placed in the substantially rectangular. compartment of the main casing.

4. n a vapor proof electric switch, a main casing having a. substantially horizontal shelf, Walls projecting upwardly from said shelf to provide a sealing liquid compartment, an insulating base secured in said walls, contacts mounted on the upper side of said base, a strap extending over said base and carrying a guide member, a switch operator extending through openings in said shelf and said base and extending into said guide member, a contact carried by said operator and cooperating with said irst contacts, and a cover mounted on said shelf.

5. A switch casing comprising a main casing having a base and walls providing a wire' EARL L. BUKER. 

